Fix double-space period, shift double-tap; settings; letters from system keymap

- Double-space replaced the space via a Backspace keysym, which clients
  apply after the commit: use delete_surrounding_text with the commit
- Tests use a shared FakeEngine that applies ops to a simulated field
- Double-tap shift locks at a sentence start; typing between taps doesn't
- Organization name set: config lives in ~/.config/sloposk/
- Settings (auto-capitalization, double-space period) with a ⚙ panel
- Letter rows come from the compositor's XKB keymap; other letters of the
  layout become long-press alternates; globe switches the system layout
  over org.kde.keyboard
- One JSON template for non-letter layers; stretch keys even out rows

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/input/KeyboardController.cpp

@@ -3,7 +3,6 @@
 
 #include "engine/InputEngine.h"
 #include "layout/LayoutModel.h"
-#include "layout/LayoutRepository.h"
 
 #include <xkbcommon/xkbcommon-keysyms.h>
 
@@ -17,15 +16,11 @@ namespace {
 constexpr qsizetype MaxTextBefore = 256;
 }
 
-KeyboardController::KeyboardController(InputEngine &engine, LayoutModel &model,
-                                       const LayoutRepository &layouts, QObject *parent)
+KeyboardController::KeyboardController(InputEngine &engine, LayoutModel &model, QObject *parent)
     : QObject(parent)
     , m_engine(engine)
     , m_model(model)
-    , m_layouts(layouts)
 {
-    if (!m_layouts.layouts().isEmpty())
-        m_model.setLayout(m_layouts.layouts().first());
     connect(&m_backspaceRepeater, &KeyRepeater::repeat, this, &KeyboardController::deleteBackward);
 }
 
@@ -79,7 +74,7 @@ void KeyboardController::keyUp(const KeyDef &key, KeyOutput output, const QStrin
         autoCapitalize();
         break;
     case KeyType::Globe:
-        nextLayout();
+        Q_EMIT nextLayoutRequested();
         break;
     case KeyType::Dismiss:
         Q_EMIT dismissRequested();
@@ -130,26 +125,25 @@ void KeyboardController::setContext(const TextContext &context)
     autoCapitalize();
 }
 
-void KeyboardController::nextLayout()
+void KeyboardController::setOptions(const TypingOptions &options)
 {
-    const auto &layouts = m_layouts.layouts();
-    if (layouts.size() < 2)
-        return;
-    m_layoutIndex = int((m_layoutIndex + 1) % layouts.size());
-    m_model.setLayout(layouts[m_layoutIndex]);
+    m_options = options;
+    autoCapitalize();
 }
 
 void KeyboardController::typeText(const QString &text)
 {
-    if (text == u" " && m_context.isProse() && TextRules::wantsDoubleSpacePeriod(m_textBefore)) {
-        m_engine.sendKeysym(XKB_KEY_BackSpace);
+    if (text == u" " && m_options.doubleSpacePeriod && m_context.isProse()
+        && TextRules::wantsDoubleSpacePeriod(m_textBefore)) {
+        // "word " + space → "word. ", replacing the first space in place.
+        m_engine.replaceBeforeCursor(QStringLiteral(" "), QStringLiteral(". "));
         m_textBefore.chop(1);
-        typeText(QStringLiteral(". "));
-        return;
+        m_textBefore += QStringLiteral(". ");
+    } else {
+        m_engine.commitText(text);
+        m_textBefore += text;
     }
-
-    m_engine.commitText(text);
-    m_textBefore = (m_textBefore + text).right(MaxTextBefore);
+    m_textBefore = m_textBefore.right(MaxTextBefore);
     changeShift([&] { m_shift.characterTyped(); });
     autoCapitalize();
 }
@@ -164,7 +158,8 @@ void KeyboardController::deleteBackward(bool wholeWord)
 
 void KeyboardController::autoCapitalize()
 {
-    const bool capitalize = m_context.allowsAutoCapitalization() && TextRules::startsSentence(m_textBefore);
+    const bool capitalize = m_options.autoCapitalize && m_context.allowsAutoCapitalization()
+                            && TextRules::startsSentence(m_textBefore);
     changeShift([&] { m_shift.setAutomatic(capitalize); });
 }